Gas bearings

ABSTRACT

A gas bearing for carrying a work load to any desired location including a circular housing having a cavity in which is arranged spaced grooves separated by ribs or lands. The bearing also has a peripheral flange which extends upwardly from the body of the housing and receives a porous plate which engages the lands and covers the grooves. Means are also provided for passing a gas ino the housing. When the bearing plate is inverted, the porous plate rests on a track or base plate and when gas passes through the porous plate, the bearing may be easily rotated or moved in a linear direction . The bearing may be of any desired size, such as from approximately one-fourth inch in diameter up to the requirement of the load to be carried in relation to the avaialbel gas supply. Two or more of the bearings may be used in tandem when the load so requires. To protect the bearing when the load is heavy, a plate which carries the work or forms part of it is provided with a counter bore which is held in spaced relation to the base plate by resilient means, such as a Bellevile washer, the lower portion of which surrounds a boss on the bearing, while work, such as shearing, stamping or forging is being performed on the load, the bottom portion of the plate surrounding the bearing is moved into engagement with the base plate. The resilient means, however, prevents the weight of the load from collapsing the bearing and this is particularly true with respect to the porous plate which is maintained intact. When the work force on the load isterminated, the resilient means again maintains the load in spaced relation to the base plate at which time the load upon which work has been performed may again be moved to any desired position.

United States Patent [191 Weichsel 1111 3,744,858 July 10, 1973 [52] US.Cl 308/5 R, 308/9, 308/D1G. l [51] Int. Cl. Fl6c 17/00 [58] Field ofSearch 308/5, 9, 122, DlG. l;

i80ll 16-125; 269120 [56] References Cited UNITED STATES PATENTS 10/1969Werchsel 308/5 R 6/1964 Kohler 308/5 R 3,484,064 12 1969 Koenig, 111308/5 R 3,325,229 6/1967 Webb 308/5 R 3,384,425 5/1968 Brown 308/5 R3,398,996 8/1968 Wucherer 308/9 3,015,524 2/1962 Slayter et al 308/9FOREIGN PATENTS OR APPLICATIONS 1,203,842 9/1970 Great Britain 308/5Primary Examiner-Charles J. Myhre Assistant Examiner--R. H. LazarusAttorney-John Mahoney [5 7] ABSTRACT A gas bearing for carrying a workload to any desired location including a circular housing having acavity in which is arranged spaced grooves separated by ribs or lands.The bearing also has a peripheral flange which extends upwardly from thebody of the housing and receives a porous plate which engages the landsand covers the grooves. Means are also provided for passing a gas inothe housing. When the bearing plate is inverted, the porous plate restson a track or base plate and when gas passes through the porous plate,the bearing may be easily rotated or moved in a linear direction Thebearing may be of any desired size, such as from approximatelyone-fourth inch in diameter up to the requirement of the load to becarried in relation to the avaialbel gas supply. Two or more of thebearings may be used in tandem when the load so requires. To protect thebearing when the load is heavy, a plate which carries the work or formspart of it is provided with a counter bore which is held in spacedrelation to the base plate by resilient means, such as a Bellevilewasher, the lower portion of which surrounds a boss on the bearing,while work, such as shearing, stamping or forging is being performed onthe load, the bottom portion of the plate surrounding the bearing ismoved into engagement with the base plate. The resilient means, however,prevents the weight of the load from collapsing the bearing and this isparticularly true with respect to the porous plate which is maintainedintact. When the work force on the load isterminated, the resilientmeans again maintains the load in spaced relation to the base plate atwhich time the load upon which work has been performed may again bemoved to any desired position.

5 Claims, 5 Drawing Figures Pmimaum 3.744.858

MEI 1 0f 2 INVENTOR. RICHARD H. WE/CHSEL A TTORNE Y PAIENIE JUL 1 01913SIEEIZ'IIZ AM A A an INVENTOR. CHARD H. WE/CHSEL A TTORNE Y GAS BEARINGSThe present invention relates to gas bearings, such as air, engineexhaust gases, or the like, and more particularly to a gas bearing whichmay be rotated or moved in a linear direction and which includes meansassociated with the bearing for protecting it from collapsing when workis being performed on a comparatively heavy load carried by the bearing.

In U.S. Pat. No. 3,475,065 granted to me on Oct. 28, 1969, a gas bearingof the single plane, linear movable type is disclosed. Such bearingsinclude a machinable housing having a cavity therein in which aplurality of grooves are trappaned which grooves are separated by landsor ribs of substantially the same width as the grooves. The bearing alsoincludes a plate having rcstrictive pores therein fitting within thecavity of the housing which engages the lands and covers the grooves andis held in place by fastening means, such as screws, extending throughthe housing. The housing as shown in my prior patent is also providedwith a tapped opening through which a gas is passed into-the grooves sothat when the housing is inverted and placed upon a Hat stationary basemember, the gas can be passed through a substantial area of the porousplate to thereby facilitate the linear movement of the housing inopposite directions. In my previous patent, however, the bearing islimited to a linear motion that is in direct relation to the air supplyavailable to it in proportion to the projecting inches of area of itswork force. In commercial use, such bearings would be desirable if theycould be used for carrying a load, such as. one that would move the workinto a suitable fixture for holding it in place while work is performedthereon, such as shearing, stamping, or punching.

In accordance. with the present invention, resilient means associatedwith the housing of the bearing is provided for protecting the bearingfrom heavy objects supported thereon while work is being performed onthe load. It is therefore not necessary to remove the load from thebearing while work is being performed thereon. My improved hearing maybe moved either in a linear direction or rotated to convey the work to adesired location where it may be held in place by any suitable fixturewhile work is being performed thereon.

It is therefore an object of the present invention to provide resilientmeans arranged between a load and a bearing for protecting the bearingwhile work is being performed upon the load.

Another object of my invention is to provide an improved gas bearing forconveying a comparatively heavy load or a work plate carrying such aload to a desired location where it may be held in place by any suitablemeans, such as a press, while work, such as shearing, stamping, punchingor forging is being performed thereon, without removing the work for thebearing and in which resilient means are provided for preventingcollapse of the bearing and particularly the porous plate during suchoperations.

My invention will be better understood by reference to the accompanyingdrawings in which:

FIG. 1 is a plan view of a portion of a housing;

FIG. 2 is a cross sectional view taken on a plane passing through theline 2-2 of FIG. 1;

FIG. 3 is a bottom plan view of the housing shown in FIG. 2;

FIG. 4 is an exploded view with parts broken away of my improved bearingincluding cross sectional views of the tract on which the bearing ridesand a plate for supporting or forming part of the load; and

FIG. 5 is a cross sectional view of the parts shown in FIG. 4 in theirassembled position with the plate for carrying the load and the loadarranged over the bearing and being held in spaced relation to the trackby resilient means.

As illustrated in FIGS. 1 to 3, the gas bearing is somewhat similar tothat shown in my prior patent with the exception that it may be eitherrotated or moved in a linear direction. As shown, it consists of acircular housing 1 having an upwardly extending peripheral flange 2which housing may be formed of any suitable metal, such as steel,aluminum, or bronze, and is trappaned out to form a plurality ofcircular grooves 3 separated by circular lands or ribs 4, each of whichgrooves communicates with tapped openings 5 and 6 through a narrowopening 7. A gas, such as air, may be supplied to the circular groovesfrom either or both of the tapped openings 5 and 6. When the opening 5is obstructed by the load plate as shown in FIG. 5, however, thatopening may be closed with a threaded plug or closure.

In utilizing my improved bearing shown in FIGS. 1 to 3, it is invertedas shown in FIGS. 4 and 5 and a porous plate 8 is arranged within theperipheral flange 2 of the housing and covers the grooves and lands 3and 4 and is secured to the housing by suitable means, such as screws 9,which extend through the porous plate and the lands and terminate withinthe housing.

As shown, the heads of the screws are countersunk so as not to interferewith the linear or circular motion of the bearing over a base plate 10which base plate may be formed of any snitable smooth material, such asa rail, or granite.

While the porous plate may be formed of any suitable material affordingsufficient feed therethrough to provide and sustain a substantiallyuniform film between the plate 8 and the base plate 10 upon which it ismovable, it preferably is composed of a commercially available materialwhich consists of a body composed of copper spheres of approximately 100mesh and of substantially uniform size which are encapsulated withsintered tin particles. In preparing the porous plate 8, thespherically-shaped copper particles and the tin particles which are ofapproximately 200 mesh are first pressed into a unitary structure andsufficient heat is applied to sinter the tin. A temperature ofapproximately l,535 Fahrenheit may be used. The temperature, however,should not be sufficient to liquefy the copper. The copper thereforeretains its spherical shape and is encapsulated with sintered tinparticles to form gas restrictive pores in which a gas passing throughthe plate meets its maximum resistance which is evidenced by asubstantial pressure drop. After the gas passes outwardly through thegas restrictive pores, it expands to form a thin non-turbulent filmwhich lies in close proximity to the outside surface of the porous plate8.

In preparing plate 8, the small copper spheres preferably constitute themajor proportion of the plate and while I do not desire to be limited toany particular proportions, the copper sphere may be present in anamount ranging from approximately 60 percent to percent and the tin inproportions ranging from approximately l0 percent to 40 percent. Forinstance, the porous plate 8 may be composed of approximately 90 percentcopper spheres and percent of sintered tin which encapsulates the copperspheres to provide venturi-shaped restrictive pores through which thegas passes.

To properly supply the porous metal plate with a sufficient amount ofgas, the construction should be of a nature to allow the pressure headto be uniform at the working surface. To obtain this uniform head, thenormal linear wall thickness of the plate 8 should be in keeping withthat which is required to support the static or at rest load at theworking surface. Having thus established the lateral wall thickness ofplate 8, this linear measurement should constitute the width of both thegrooves and the ribs or lands 4. As shown the depth of the grooves 3should be approximately one-half of the width of a groove. With such anarrangement, a gas, such as air, flowing from tapped openings 5 or 6 isfirst restricted by the orifices in the plate 8 and then expands to forma thin nonturbulent uniform film between the plate 8 and the flat baseplate 10.

In practicing my invention, the housing 1 of the bearing is preferablycircular and may vary from approximately one-fourth inch in diameter tothe requirement of the load in relation to the available air supplyalthough if desired two or more circular bearings may be used in tandemto support larger loads which are to be moved in a linear direction.

The bearing is particularly adapted to convey loads in a linearly orrotatable direction to a fixture in which the load may beheld in placeand work performed thereon without removing it from the bearing. Forthis purpose, the load may consist of a work plate or table 11 formingpart of the work or a plate on which the work is carried and is providedwith a counter bore 12 for receiving the bearing. I

In accordance with my invention the bearing is capable of carrying theload when the load rests upon the bearing without any work being donethereon in which case, the portion of the work plate adjacentits'counter bore may be in the position shown in FIG. 5. To preventcollapse of the bearing, however, when work is being performed on theload forming part of the work plate or being carried by the work plate,such as shearing, stamping, or punching, the work plate is spaced fromthe upper wall of the bearing by resilient means. The resilient meansmay be of any suitable type, As shown in FIGS. 4 and 5, it is in theform of a Belleville washer 13 which is of the shape of the frustrum ofa cone with upper and lower openings, the lower portion of which washersurrounds the boss 14 on the bearing.

To enable the table 12 and the work thereon to be moved with the gasbearing, the resilient means is strong enough to maintain the portion ofthe work table which surrounds the counter bore above the base plate.When work is to be performed on the load which may, for example, be acomparatively heavy metal member, such as a jig or a boring mill,together with a work table for carrying such loads, the weight of theload forces the Belleville washer downwardly to such an extent that thelower portion of the work table adjacent its counter bore engages thebase plate. The table 11 for supporting the work and the resilient meansextending between the work plate and the bearing, however, prevent theload from crushing the bearing and this is particularly true withrespect to the porous plate. After the work is performed, the load maybe released from the fixture and moved to any desired position. As shownin the drawings, the work piece may be in the form of a plate forcarrying a load 15, such as a casting or forging, as shown in FIG. 5 orwhich forms part of the load, and is provided with an opening 16 thereinarranged in alignment with the tapped opening 6 in the bearing so that agas may be introduced through the socket 6 and into a plenum chamberwhich as shown is in the form of a channel 15 to the narrow openings andgrooves 3 and then through the porous plate 8 to form a thin filmbetween the porous plate and the base plate 10.

What is claimed is:

l. A gas bearing including a housing having a cavity therein and aperipheral flange surrounding the cavity, means providing a plurality ofspaced grooves within the cavity which are separated by lands, a porousplate arranged within said cavity which engages said lands and coverssaid grooves, means for securing said porous plate to said housing, abase plate upon which the porous plate rests, means whereby a gas may bepassed into said housing which passes through said porous plate andwhich forms a bearing between said porous plate and the base plate, aload including a work plate to be moved which work plate has a counterbore surrounding said bearing and resilient means interposed between thetop of said bearing and the work plate that has sufficient strength tomaintain the work plate in spaced relation to said base plate so'thatthe bearing may be moved to a desired position when the load is thereon.

2. A gas bearing as defined in claim 1 in which the load when workedupon has sufficient weight to move the portions of the work platesurrounding the bearing into engagement with said base plate to therebyprevent movement of the bearing upon the base plate while work is beingperformed upon the load and said resilient means having sufficientstrength to prevent damage to the bearing while work is being performedupon the load.

3. A bearing as defined in claim I in which the bearing has an upperboss thereon, a plenum chamber therein, and a socket passing throughsaid boss and communicating with said plenum chamber, and said workplate having an aperture therein which is in alignment with the socketin said bearing so that gas may be passed through said opening andsocket into the plenum chamber of said bearing, and the resilient meansis a Bellesville washer having upper and lower openings therein with itslower end portion surrounding said boss and its upper end portionengaging the lower face of the upper wall of the counter bore of thework plate and surrounding the opening in the work plate.

4. A gas bearing as defined in claim 1 in which the bearing is circularin shape so that it may be moved either in a linear direction or rotatedin a circular directlon.

5. A gas bearing as defined in claim 1 in which the grooves and lands insaid housing are of substantially the same width as the thickness of theporous plate.

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1. A gas bearing including a housing having a cavity therein and aperipheral flange surrounding the cavity, means providing a plurality ofspaced grooves within the cavity which are separated by lands, a porousplate arranged within said cavity which engages said lands and coverssaid grooves, means for securing said porous plate to said housing, abase plate upon which the porous plate rests, means whereby a gas may bepassed into said housing which passes through said porous plate andwhich forms a bearing between said porous plate and the base plate, aload including a work plate to be moved which work plate has a counterbore surrounding said bearing and resilient means interposed between thetop of said bearing and the work plate that has sufficient strength tomaintain the work plate in spaced relation to said base plate so thatthe bearing may be moved to a desired position when the load is thereon.2. A gas bearing as defined in claim 1 in which the load when workedupon has sufficient weight to move the portions of the work platesurrounding the bearing into engagement with said base plate to therebyprevent movement of the bearing upon the base plate while work is beingperformed upon the load and said resilient means having sufficientstrength to prevent damage to the bearing while work is being performedupon the load.
 3. A bearing as defined in claim 1 in which the bearinghas an upper boss thereon, a plenum chamber therein, and a socketpassing through said boss and communicating with said plenum chamber,and said work plate having an aperture therein which is in alignmentwith the socket in said bearing so that gas may be passed through saidopening and socket into the plenum chamber of said bearing, and theresilient means is a Bellesville washer having upper and lower openingstherein with its lower end portion surrounding said boss and its upperend portion engaging the lower face of the upper wall of the counterbore of the work plate and surrounding the opening in the work plate. 4.A gas bearing as defined in claim 1 in which the bearing is circular inshape so that it may be moved either in a linear direction or rotated ina circular direction.
 5. A gas bearing as defined in claim 1 in whichthe grooves and lands in said housing are of substantially the samewidth as the thickness of the porous plate.